From: Brian McGahan (bmcgahan@internetworkexpert.com)
Date: Wed Dec 10 2003 - 19:56:37 GMT-3
Ken,
Local-AS is a special case of no-export used for confederation.
When a prefix is tagged with the community local-as it will not be
advertised outside of the sub-as inside a confederation. No-export when
used in this case will allow a prefix to be passed between sub-ASs but not
outside the main AS.
When not inside a confederation local-as behaves the same as
no-export.
HTH,
Brian McGahan, CCIE #8593
bmcgahan@internetworkexpert.com
Internetwork Expert, Inc.
http://www.InternetworkExpert.com
Toll Free: 877-224-8987
Direct: 708-362-1418 (Outside the US and Canada)
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> Ken.Farrington@barclayscapital.com
> Sent: Wednesday, December 10, 2003 3:52 PM
> To: ccielab@groupstudy.com
> Subject: BGP Communities - no-export and local-as *Spot the difference*
>
> Hey dudes, not long till larger time!
>
> What is the difference between these two communities. I have tested this
> in
> my lab between varios iBGP/eBGP peers and they both prevent the one
> network
> configured 69.69.69.0 from being advertised to the eBGP peer.
>
> So which one do i use?
>
> BRs,
> Ken
>
> --------------------------------
> Config sample below
> --------------------------------
> !
> interface Loopback69
> ip address 69.69.69.69 255.255.255.0
> !
> interface Loopback70
> ip address 70.70.70.70 255.255.255.0
> !
> !
> router bgp 13
> no synchronization
> bgp log-neighbor-changes
> network 69.69.69.0 mask 255.255.255.0
> network 70.70.70.0 mask 255.255.255.0
> neighbor 155.195.4.4 remote-as 13
> neighbor 155.195.4.4 update-source Loopback0
> neighbor 155.195.4.4 send-community
> neighbor 155.195.4.4 route-map set-noexport out
> no auto-summary
> !
> !
> access-list 10 permit 69.69.69.0
> !
> route-map set-noexport permit 10
> match ip address 10
> set community no-export
> !
> route-map set-noexport permit 20
> !
> !
> !
> route-map set-localas permit 10
> match ip address 10
> set community local-AS
> !
> route-map set-localas permit 20
>
>
> ------------------------------------------------------------------------
> For more information about Barclays Capital, please
> visit our web site at http://www.barcap.com.
>
>
> Internet communications are not secure and therefore the Barclays
> Group does not accept legal responsibility for the contents of this
> message. Although the Barclays Group operates anti-virus programmes,
> it does not accept responsibility for any damage whatsoever that is
> caused by viruses being passed. Any views or opinions presented are
> solely those of the author and do not necessarily represent those of the
> Barclays Group. Replies to this email may be monitored by the Barclays
> Group for operational or business reasons.
>
> ------------------------------------------------------------------------
>
> _______________________________________________________________________
> Please help support GroupStudy by purchasing your study materials from:
> http://shop.groupstudy.com
>
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
This archive was generated by hypermail 2.1.4 : Sat Jan 03 2004 - 08:25:39 GMT-3